Chrysanthemum stunt viroid(CSVD00)
Hosts
Important note about the classification of host plants in GD:
Categories have been assigned by the EPPO Secretariat on the basis of available data at the time of entry. They correspond to a qualitative evaluation of the importance of the host plant for the pest concerned and remain indicative only.
Further explanation of categories is available in the guide.
Categories have been assigned by the EPPO Secretariat on the basis of available data at the time of entry. They correspond to a qualitative evaluation of the importance of the host plant for the pest concerned and remain indicative only.
Further explanation of categories is available in the guide.
| Organism | Type | |
|---|---|---|
| Chrysanthemum x morifolium (CHYHO) | Major host | |
* Diener TO and Lawson RH (1973) Chrysanthemum stunt: a viroid disease. Virology, 51, 94–101. * Gobatto D, Araújo de Oliveira L, Andrade de Siqueira Franco D, Velásquez N, Daròs J-A, Eiras M (2019) Surveys in the chrysanthemum production areas of Brazil and Colombia reveal that weeds are potential reservoirs of Chrysanthemum stunt viroid. Viruses 11, 355. doi:10.3390/v11040355 * Diener TO, Lawson RH (1973) Chrysanthemum stunt: a viroid disease. Virology, 51, 94–101 | ||
| Solanum nigrum (SOLNI) | Wild/Weed | |
* Matsushita Y, Yanagisawa H, Khiutti A, Mironenko N, Ohto Y, Afanasenko O (2021) Genetic diversity and pathogenicity of potato spindle tuber viroid and chrysanthemum stunt viroid isolates in Russia. European Journal of Plant Pathology 161(3), 529-542. ------- first detection on S. nigrum. | ||
| Argyranthemum frutescens (CHYFR) | Host | |
* Torchetti EM, Navarro B, Trisciuzzi VN, Nuccitelli L, Silletti MR, Di Serio F (2012) First report of Chrysanthemum stunt viroid in Argyranthemum frutescens in Italy. Journal of Plant Pathology, 94, 451–454. * Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Argyranthemum maderense (AZGMA) | Host | |
* Wang QC, Lee Y, Sivertsen A, Skjeseth G, Zhang ZB, Haugslien S, Clark JL, Spetz C, Blystad DR (2013) Cryotherapy could not eradicate Chrysanthemum stunt viroid from infected Argyranthemum maderense'Yellow Empire'. InII International Symposium on Plant Cryopreservation. ISHS Acta Horticulturae 10391039, (pp. 201-208). (abst.) | ||
| Argyranthemum sp. (AZGSS) | Host | |
* Zhang Z, Lee Y, Spetz C, Clarke JL, Wang Q, Blystad DR (2014) Invasion of shoot apical meristems by Chrysanthemum stunt viroid differs among Argyranthemum cultivars. Frontiers in Plant Science 6, 53. https://doi.org/10.3389/fpls.2015.00053 | ||
| Chrysanthemum (1CHYG) | Host | |
* Gobatto D, Araújo de Oliveira L, Andrade de Siqueira Franco D, Velásquez N, Daròs J-A, Eiras M (2019) Surveys in the chrysanthemum production areas of Brazil and Colombia reveal that weeds are potential reservoirs of Chrysanthemum stunt viroid. Viruses 11, 355. doi:10.3390/v11040355 ------- As Dendranthema. | ||
| Chrysanthemum crassum (DDMCR) | Host | |
* Matsushita Y, Tsukiboshi T, Ito Y, Chikuo Y (2007) Nucleotide Sequences and Distribution of Chrysanthemum Stunt Viroid in Japan. Journal of the Japanese Society for Horticultural Science 76 (4), 333–337. | ||
| Chrysanthemum indicum (CHYIN) | Host | |
* Matsushita Y, Tsukiboshi T, Ito Y, Chikuo Y (2007) Nucleotide Sequences and Distribution of Chrysanthemum Stunt Viroid in Japan. Journal of the Japanese Society for Horticultural Science 76 (4), 333–337. | ||
| Chrysanthemum japonense (DDMJA) | Host | |
* Matsushita Y, Tsukiboshi T, Ito Y, Chikuo Y (2007) Nucleotide Sequences and Distribution of Chrysanthemum Stunt Viroid in Japan. Journal of the Japanese Society for Horticultural Science 76 (4), 333–337. | ||
| Chrysanthemum lavandulifolium (DDMBO) | Host | |
* Osaka M, Itabashi T, Chiba N, Sumitomo K, Matsushita Y (2021) The effects on adventitious root formation caused by chrysanthemum stunt viroid in Chrysanthemum morifolium and C. seticuspe. Journal of Phytopathology 169(11-12), 710-715. ------- as Chrysanthemum seticuspe. | ||
| Chrysanthemum makinoi (CHYMK) | Host | |
* Matsushita Y, Tsukiboshi T, Ito Y, Chikuo Y (2007) Nucleotide Sequences and Distribution of Chrysanthemum Stunt Viroid in Japan. Journal of the Japanese Society for Horticultural Science 76 (4), 333–337. ------- as C. makinoi and C. wakasaense. | ||
| Chrysanthemum yoshinaganthum (CHYYO) | Host | |
* Matsushita Y, Tsukiboshi T, Ito Y, Chikuo Y (2007) Nucleotide Sequences and Distribution of Chrysanthemum Stunt Viroid in Japan. Journal of the Japanese Society for Horticultural Science 76 (4), 333–337. | ||
| Chrysanthemum zawadskii (CHYZA) | Host | |
* Matsushita Y, Tsukiboshi T, Ito Y, Chikuo Y (2007) Nucleotide Sequences and Distribution of Chrysanthemum Stunt Viroid in Japan. Journal of the Japanese Society for Horticultural Science 76 (4), 333–337. | ||
| Chrysanthemum zawadzkii subsp. zawadzkii (DDMWE) | Host | |
* Matsushita Y, Tsukiboshi T, Ito Y, Chikuo Y (2007) Nucleotide Sequences and Distribution of Chrysanthemum Stunt Viroid in Japan. Journal of the Japanese Society for Horticultural Science 76 (4), 333–337. ------- as Chrysanthemum weyrichii. | ||
| Dahlia (1DAHG) | Host | |
* Asano S, Matsushita Y, Hirayama Y, Naka T (2015) Simultaneous detection of Tomato spotted wilt virus, Dahlia mosaic virus and Chrysanthemum stunt viroid by multiplex RT‐PCR in dahlias and their distribution in Japanese dahlias. Letters in Applied Microbiology 61 (2), 113-120. * Asano S, Yoshida K, Naka T, Hirayama Y, Matsushita Y (2020) The distribution and nucleotide sequences of chrysanthemum stunt viroid in dahlia fields in Japan and the effect of its infection on the growth of dahlias. European Journal of Plant Pathology volume 156(1), 245–256 (2020). https://doi.org/10.1007/s10658-019-01883-z * Nakashima A, Hosokawa M, Maeda S, Yazawa S (2007) Natural infection of Chrysanthemum stunt viroid in dahlia plants. Journal of General Plant Pathology 73, 225–227 | ||
| Oxalis latifolia (OXALA) | Host | |
* Gobatto D, Araújo de Oliveira L, Andrade de Siqueira Franco D, Velásquez N, Daròs J-A & Eiras M (2019) Surveys in the Chrysanthemum Production Areas of Brazil and Colombia Reveal That Weeds Are Potential Reservoirs of Chrysanthemum Stunt Viroid. Viruses, 11, 355. doi:10.3390/v11040355 -------Plants of Oxalis latifolia and chrysanthemum naturally infected with CSVd were found in chrysanthemum fields in Colombia. | ||
| Pericallis x hybrida (SENCR) | Host | |
* EFSA Panel on Plant Health (2012) Scientific Opinion on the risk to plant health posed by Chrysanthemum stunt viroid for the EU territory, with identification and evaluation of risk reduction options. EFSA Journal. 10(12), 3027. * Verhoeven JThJ (2010) Identification and epidemiology of pospiviroids. Thesis. Wageningen University, Wageningen, Netherlands, 136 pp. ISBN 978-90-8585-623-8. | ||
| Petunia hybrids (PEUHY) | Host | |
* Verhoeven JTJ, Arts MSJ, Owens RA, Roenhorst JW (1998) Natural infection of petunia by chrysanthemum stunt viroid. Euroean Journal of Plant Pathology 104, 383–386. | ||
| Portulaca oleracea (POROL) | Host | |
* Gobatto D, Araújo de Oliveira L, Andrade de Siqueira Franco D, Velásquez N, Daròs J-A, Eiras M (2019) Surveys in the chrysanthemum production areas of Brazil and Colombia reveal that weeds are potential reservoirs of Chrysanthemum stunt viroid. Viruses 11, 355. https://doi.org/10.3390/v11040355 | ||
| Solanum laxum (SOLJM) | Host | |
* Verhoeven JTJ, Jansen CCC, Roenhorst JW (2006) First report of Potato virus M and Chrysanthemum stunt viroid in Solanum jasminoides. Plant Disease 90(10), 1359. https://doi.org/10.1094/PD-90-1359A. ------- host as Solanum jasminoides. | ||
| Solanum tuberosum (SOLTU) | Host | |
* Runia WT, Peters D (1980) The response of plant species used in agriculture and horticulture to viroid infections. Netherlands Journal of Plant Pathology, 86, 135–146. ------- experimental host. * Matsushita Y, Yanagisawa H, Khiutti A, Mironenko N, Ohto Y, Afanasenko O (2019) First report of chrysanthemum stunt viroid isolated from potato (Solanum tuberosum) plants in Russia. Journal of General Plant Pathology, https://doi.org/10.1007/s10327-019-00851-z ------- asymptomatic. First report of natural infection on potato. | ||
| Tanacetum parthenium (CHYPA) | Host | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. -------as Chrysanthemum parthenium, Chrysanthemum parthenium f. flosculosum, Chrysanthemum praealtum. | ||
| Verbena sp. (VEBSS) | Host | |
* Bostan H, Nie X and Singh RP(2004) An RT-PCR primer pair for the detection of pospiviroids and its application in surveying ornamental plants for viroids. Journal of Virological Methods, 116, 189–193 | ||
| Vinca major (VINMA) | Host | |
* Bostan H, Nie X and Singh RP (2004) An RT-PCR primer pair for the detection of pospiviroids and its application in surveying ornamental plants for viroids. Journal of Virological Methods, 116, 189–193. * Nie X, Singh RP and Bostan H (2005) Molecular cloning, secondary structure, and phylogeny of three pospiviroids from ornamental plants. Canadian Journal of Plant Pathology, 27, 592–602. | ||
| Achillea millefolium (ACHMI) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Achillea ptarmica (ACHPT) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Ageratum sp. (AGESS) | Experimental | |
* EFSA Panel on Plant Health (2012) Scientific Opinion on the risk to plant health posed by Chrysanthemum stunt viroid for the EU territory, with identification and evaluation of risk reduction options. EFSA Journal. 10(12), 3027. (Quoting: Henkel J and Sänger HL, 1995. NCBI GenBank Accession Z68201.) | ||
| Ajania pacifica (CHYPC) | Experimental | |
* Matsushita Y, Penmetcha KKR (2009) In vitro-transcribed chrysanthemum stunt viroid RNA is infectious to chrysanthemum and other plants. Phytopathology 99, 58-66. ------- as Chrysanthemum pacificum. * Matsushita Y, Aoki k, Sumitomoa K (2012) Selection and inheritance of resistance to Chrysanthemum stunt viroid. Crop Protection 35, 1-4 ------- as Chrysanthemum pacificum. | ||
| Ajania shiwogiku (CHYSW) | Experimental | |
* Matsushita Y, Aoki k, Sumitomoa K (2012) Selection and inheritance of resistance to Chrysanthemum stunt viroid. Crop Protection 35, 1-4 | ||
| Amaranthus viridis (AMAVI) | Experimental | |
* Gobatto D, Araújo de Oliveira L, Andrade de Siqueira Franco D, Velásquez N, Daròs J-A, Eiras M (2019) Surveys in the chrysanthemum production areas of Brazil and Colombia reveal that weeds are potential reservoirs of Chrysanthemum stunt viroid. Viruses 11, 355. https://doi.org/10.3390/v11040355 | ||
| Ambrosia trifida (AMBTR) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Arctotis fastuosa (VEDFA) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. ------ as Venidium fastuosum. | ||
| Atropanthe sinensis (ATFSI) | Experimental | |
* Kryczynski S and Paduch-Cichal E (1987) A comparative study of four viroids of plants. Journal of Phytopathology 120, 121–129. ------ as Scolopia sinensis | ||
| Benincasa hispida (BNCHI) | Experimental | |
* Runia WT, Peters D (1980) The response of plant species used in agriculture and horticulture to viroid infections. Netherlands Journal of Plant Pathology, 86, 135–146. -------as Benincasa cerifera. | ||
| Capsicum annuum (CPSAN) | Experimental | |
* Runia WT, Peters D (1980) The response of plant species used in agriculture and horticulture to viroid infections. Netherlands Journal of Plant Pathology, 86, 135–146. | ||
| Cardamine bonariensis (CARBO) | Experimental | |
* Gobatto D, Araújo de Oliveira L, Andrade de Siqueira Franco D, Velásquez N, Daròs J-A, Eiras M (2019) Surveys in the chrysanthemum production areas of Brazil and Colombia reveal that weeds are potential reservoirs of Chrysanthemum stunt viroid. Viruses 11, 355. https://doi.org/10.3390/v11040355 | ||
| Catharanthus roseus (CTURO) | Experimental | |
* Gobatto D, Araújo de Oliveira L, Andrade de Siqueira Franco D, Velásquez N, Daròs J-A, Eiras M (2019) Surveys in the chrysanthemum production areas of Brazil and Colombia reveal that weeds are potential reservoirs of Chrysanthemum stunt viroid. Viruses 11, 355. https://doi.org/10.3390/v11040355 | ||
| Centaurea cyanus (CENCY) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Chrysanthemum nivellei (CHYNV) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Chrysanthemum sp. (CHYSS) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Coleostephus myconis (CHYMY) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. ------- as Chrysanthemum myconis | ||
| Cota tinctoria (ANTTI) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. ------- as Anthemis tinctoria | ||
| Cucumis sativus (CUMSA) | Experimental | |
* Runia WT, Peters D (1980) The response of plant species used in agriculture and horticulture to viroid infections. Netherlands Journal of Plant Pathology, 86, 135–146. * Walia, Y , Dhir S & Hallan V (2021) Molecular and biological characterisation of an Indian variant of Chrysanthemum stunt viroid, Archives of Phytopathology and Plant Protection, https://doi.org/10.1080/03235408.2020.1868743 | ||
| Dahlia pinnata (DAHPI) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. ------- as Dahlia variabilis. | ||
| Delairea odorata (SENMI) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. ------- as Senecio mikanioides. | ||
| Digitaria sanguinalis (DIGSA) | Experimental | |
* Gobatto D, Araújo de Oliveira L, Andrade de Siqueira Franco D, Velásquez N, Daròs J-A, Eiras M (2019) Surveys in the chrysanthemum production areas of Brazil and Colombia reveal that weeds are potential reservoirs of Chrysanthemum stunt viroid. Viruses 11, 355. https://doi.org/10.3390/v11040355 | ||
| Echinacea purpurea (RUDPU) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Emilia coccinea (EMICO) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. ------- as Emilia sagittata. | ||
| Emilia fosbergii (EMIFO) | Experimental | |
| Erigeron bonariensis (ERIBO) | Experimental | |
* Gobatto D, Araújo de Oliveira L, Andrade de Siqueira Franco D, Velásquez N, Daròs J-A, Eiras M (2019) Surveys in the chrysanthemum production areas of Brazil and Colombia reveal that weeds are potential reservoirs of Chrysanthemum stunt viroid. Viruses 11, 355. https://doi.org/10.3390/v11040355 ------- as Conyza bonariensis. | ||
| Euphorbia hirta (EPHHI) | Experimental | |
* Gobatto D, Araújo de Oliveira L, Andrade de Siqueira Franco D, Velásquez N, Daròs J-A, Eiras M (2019) Surveys in the chrysanthemum production areas of Brazil and Colombia reveal that weeds are potential reservoirs of Chrysanthemum stunt viroid. Viruses 11, 355. https://doi.org/10.3390/v11040355 ------- as Chamaesyce hirta. | ||
| Glebionis carinata (CHYCA) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. ------- as Chrysanthemum carinatum. | ||
| Glebionis coronaria (CHYCO) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Gomphrena globosa (GOMGL) | Experimental | |
* Gobatto D, Araújo de Oliveira L, Andrade de Siqueira Franco D, Velásquez N, Daròs J-A, Eiras M (2019) Surveys in the chrysanthemum production areas of Brazil and Colombia reveal that weeds are potential reservoirs of Chrysanthemum stunt viroid. Viruses 11, 355. https://doi.org/10.3390/v11040355 | ||
| Gynura aurantiaca (GYUAU) | Experimental | |
* Bachelier JC, Monsion M, Dunez J (1976) Possibilities of improving detection of chrysanthemum stunt and obtention of viroid-free plants by meristem tip culture. Acta Horticulturae, 59, 63–69. | ||
| Helianthus annuus (HELAN) | Experimental | |
* Gobatto D, Araújo de Oliveira L, Andrade de Siqueira Franco D, Velásquez N, Daròs J-A, Eiras M (2019) Surveys in the chrysanthemum production areas of Brazil and Colombia reveal that weeds are potential reservoirs of Chrysanthemum stunt viroid. Viruses 11, 355. https://doi.org/10.3390/v11040355 | ||
| Heteranthemis viscidehirta (HTMVI) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Leucanthemum lacustre (LCALA) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Leucanthemum maximum (CHYMA) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Leucanthemum vulgare (CHYLE) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Liatris pycnostachya (LTSPY) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Liatris spicata (LTSSP) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Lupinus polyphyllus (LUPPO) | Experimental | |
* Gobatto D, Araújo de Oliveira L, Andrade de Siqueira Franco D, Velásquez N, Daròs J-A, Eiras M (2019) Surveys in the chrysanthemum production areas of Brazil and Colombia reveal that weeds are potential reservoirs of Chrysanthemum stunt viroid. Viruses 11, 355. https://doi.org/10.3390/v11040355 | ||
| Mirabilis jalapa (MIBJA) | Experimental | |
* Gobatto D, Araújo de Oliveira L, Andrade de Siqueira Franco D, Velásquez N, Daròs J-A, Eiras M (2019) Surveys in the chrysanthemum production areas of Brazil and Colombia reveal that weeds are potential reservoirs of Chrysanthemum stunt viroid. Viruses 11, 355. https://doi.org/10.3390/v11040355 | ||
| Nicandra physalodes (NICPH) | Experimental | |
* Runia WT, Peters D (1980) The response of plant species used in agriculture and horticulture to viroid infections. Netherlands Journal of Plant Pathology, 86, 135–146. | ||
| Pericallis cruenta (SENCU) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Petunia axillaris (PEUAX) | Experimental | |
* Runia WT, Peters D (1980) The response of plant species used in agriculture and horticulture to viroid infections. Netherlands Journal of Plant Pathology, 86, 135–146. * Runia WT, Peters D (1980) The response of plant species used in agriculture and horticulture to viroid infections. Netherlands Journal of Plant Pathology, 86, 135–146. | ||
| Sanvitalia procumbens (SNVPR) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Senecio glastifolius (SENGF) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Solanum lycopersicum (LYPES) | Experimental | |
* Yoon JY, Baek E, Palukaitis P (2012)Are there strains of Chrysanthemum stunt viroid? Journal of Plant Pathology 94(3), 697-701. | ||
| Solanum melongena (SOLME) | Experimental | |
* Runia WT, Peters D (1980) The response of plant species used in agriculture and horticulture to viroid infections. Netherlands Journal of Plant Pathology, 86, 135–146. | ||
| Sonchus asper (SONAS) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Tanacetum balsamita (CHYBA) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Tanacetum bipinnatum (TNCBI) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Tanacetum cinerariifolium (CHYCI) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. ------- as Chrysanthemum cinerariaefolium | ||
| Tanacetum coccineum (CHYCC) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Tanacetum corymbosum (CHYCY) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Tanacetum vulgare (CHYVU) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Tithonia rotundifolia (TITRO) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Verbesina encelioides (VEEEN) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||
| Vogtia annua (TNCAN) | Experimental | |
| Zinnia elegans (ZIIEL) | Experimental | |
* Diener TO (1979) Viroids and Viroid Diseases. Wiley-Interscience, New York, 252 pp. | ||